A C-arm can be used in an operating room in order to obtain X-ray images of a patient during a surgical intervention.
The C-arm comprises between one and six degrees of freedom: up to three degrees of freedom in translation in three orthogonal planes and up to three degrees of freedom in rotation according to three orthogonal axes.
During a surgical intervention, different users may have to actuate the C-arm in order to acquire X-ray images of the patient or to remove the C-arm from the patient when no X-ray acquisition is required.
To that end, the user may have a control panel comprising a plurality of actuation buttons, each button being dedicated to a movement of the C-arm according to a respective degree of freedom. For example, each button may display a pictogram with an arrow representing schematically the direction of the corresponding movement.
Alternatively, the user may have a joystick wherein the stick can be actuated in a plurality of directions, each direction being associated with a movement of the C-arm according to a respective degree of freedom.
However, since the movement of the C-arm is complex (combination of rotation(s) and translation(s)), in some positions of the C-arm the user is not able to select the correct button(s) in view of obtaining the desired movement. This is because even if the buttons each display a pictogram, this representation of the movement is given in a generic way, i.e. relative to a rest position. However, the mental scheme of the user may not be suited to the indication provided on the buttons.
As a result, the user often selects a wrong button and thus may reach the desired position only after a succession of trial-and-error selections, which are time-consuming and potentially generative of collisions with user, patient or furniture.
In addition, the position of the user relative to the C-arm may also vary during the surgical intervention. For example, if the user is the surgeon or his assistant, the user may move from a position from which he sees the C-arm from the left to a position from which he sees the C-arm from the right, and conversely. In some cases, if the user is in a favorable point of view, the selection of the appropriate button will be intuitive, whereas if the user is in a different point of view, the selection of the correct actuation button will not be intuitive.